1. Field of the Invention
The present invention is related to an electrical bicycle, and more particularly to a transmission for an electrical bicycle.
2. Description of Related Art
A conventional transmission for an electric bicycle utilizes a planet gear assembly to transmit power from cranks. The structure of the planet gear is complex and requires a high manufacturing precision, so the cost of the planet gear is high. When the required velocity rate for different bicycles varies, the transmission needs to be replaced with another planet gear assembly. This also increases the manufacturing cost. Moreover, it is inconvenient for a manufacture to change a relative angle between the motor and a crank axle of the bicycle, because other elements must be redesigned in this situation.
Therefore, the invention provides a transmission for an electric bicycle to mitigate and/or obviate the aforementioned problems.
A main objective of the invention is to provide a transmission for an electric bicycle which has a simple and compact structure with a low cost.
Another objective of the invention is to provide a transmission for an electric bicycle which is able to change a relative angle between a motor and a crank axle.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.